xref: /dpdk/doc/guides/prog_guide/cryptodev_lib.rst (revision b55efbabe47b66f1b82395c0576531ab24b060bf)
1..  SPDX-License-Identifier: BSD-3-Clause
2    Copyright(c) 2016-2020 Intel Corporation.
3
4Cryptography Device Library
5===========================
6
7The cryptodev library provides a Crypto device framework for management and
8provisioning of hardware and software Crypto poll mode drivers, defining generic
9APIs which support a number of different Crypto operations. The framework
10currently only supports cipher, authentication, chained cipher/authentication
11and AEAD symmetric and asymmetric Crypto operations.
12
13
14Design Principles
15-----------------
16
17The cryptodev library follows the same basic principles as those used in DPDK's
18Ethernet Device framework. The Crypto framework provides a generic Crypto device
19framework which supports both physical (hardware) and virtual (software) Crypto
20devices as well as a generic Crypto API which allows Crypto devices to be
21managed and configured and supports Crypto operations to be provisioned on
22Crypto poll mode driver.
23
24
25Device Management
26-----------------
27
28Device Creation
29~~~~~~~~~~~~~~~
30
31Physical Crypto devices are discovered during the PCI probe/enumeration of the
32EAL function which is executed at DPDK initialization, based on
33their PCI device identifier, each unique PCI BDF (bus/bridge, device,
34function). Specific physical Crypto devices, like other physical devices in DPDK
35can be white-listed or black-listed using the EAL command line options.
36
37Virtual devices can be created by two mechanisms, either using the EAL command
38line options or from within the application using an EAL API directly.
39
40From the command line using the --vdev EAL option
41
42.. code-block:: console
43
44   --vdev  'crypto_aesni_mb0,max_nb_queue_pairs=2,socket_id=0'
45
46.. Note::
47
48   * If DPDK application requires multiple software crypto PMD devices then required
49     number of ``--vdev`` with appropriate libraries are to be added.
50
51   * An Application with crypto PMD instances sharing the same library requires unique ID.
52
53   Example: ``--vdev  'crypto_aesni_mb0' --vdev  'crypto_aesni_mb1'``
54
55Or using the rte_vdev_init API within the application code.
56
57.. code-block:: c
58
59   rte_vdev_init("crypto_aesni_mb",
60                     "max_nb_queue_pairs=2,socket_id=0")
61
62All virtual Crypto devices support the following initialization parameters:
63
64* ``max_nb_queue_pairs`` - maximum number of queue pairs supported by the device.
65* ``socket_id`` - socket on which to allocate the device resources on.
66
67
68Device Identification
69~~~~~~~~~~~~~~~~~~~~~
70
71Each device, whether virtual or physical is uniquely designated by two
72identifiers:
73
74- A unique device index used to designate the Crypto device in all functions
75  exported by the cryptodev API.
76
77- A device name used to designate the Crypto device in console messages, for
78  administration or debugging purposes. For ease of use, the port name includes
79  the port index.
80
81
82Device Configuration
83~~~~~~~~~~~~~~~~~~~~
84
85The configuration of each Crypto device includes the following operations:
86
87- Allocation of resources, including hardware resources if a physical device.
88- Resetting the device into a well-known default state.
89- Initialization of statistics counters.
90
91The rte_cryptodev_configure API is used to configure a Crypto device.
92
93.. code-block:: c
94
95   int rte_cryptodev_configure(uint8_t dev_id,
96                               struct rte_cryptodev_config *config)
97
98The ``rte_cryptodev_config`` structure is used to pass the configuration
99parameters for socket selection and number of queue pairs.
100
101.. code-block:: c
102
103    struct rte_cryptodev_config {
104        int socket_id;
105        /**< Socket to allocate resources on */
106        uint16_t nb_queue_pairs;
107        /**< Number of queue pairs to configure on device */
108    };
109
110
111Configuration of Queue Pairs
112~~~~~~~~~~~~~~~~~~~~~~~~~~~~
113
114Each Crypto devices queue pair is individually configured through the
115``rte_cryptodev_queue_pair_setup`` API.
116Each queue pairs resources may be allocated on a specified socket.
117
118.. code-block:: c
119
120    int rte_cryptodev_queue_pair_setup(uint8_t dev_id, uint16_t queue_pair_id,
121                const struct rte_cryptodev_qp_conf *qp_conf,
122                int socket_id)
123
124   struct rte_cryptodev_qp_conf {
125        uint32_t nb_descriptors; /**< Number of descriptors per queue pair */
126        struct rte_mempool *mp_session;
127        /**< The mempool for creating session in sessionless mode */
128        struct rte_mempool *mp_session_private;
129        /**< The mempool for creating sess private data in sessionless mode */
130    };
131
132
133The fields ``mp_session`` and ``mp_session_private`` are used for creating
134temporary session to process the crypto operations in the session-less mode.
135They can be the same other different mempools. Please note not all Cryptodev
136PMDs supports session-less mode.
137
138
139Logical Cores, Memory and Queues Pair Relationships
140~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
141
142The Crypto device Library as the Poll Mode Driver library support NUMA for when
143a processor’s logical cores and interfaces utilize its local memory. Therefore
144Crypto operations, and in the case of symmetric Crypto operations, the session
145and the mbuf being operated on, should be allocated from memory pools created
146in the local memory. The buffers should, if possible, remain on the local
147processor to obtain the best performance results and buffer descriptors should
148be populated with mbufs allocated from a mempool allocated from local memory.
149
150The run-to-completion model also performs better, especially in the case of
151virtual Crypto devices, if the Crypto operation and session and data buffer is
152in local memory instead of a remote processor's memory. This is also true for
153the pipe-line model provided all logical cores used are located on the same
154processor.
155
156Multiple logical cores should never share the same queue pair for enqueuing
157operations or dequeuing operations on the same Crypto device since this would
158require global locks and hinder performance. It is however possible to use a
159different logical core to dequeue an operation on a queue pair from the logical
160core which it was enqueued on. This means that a crypto burst enqueue/dequeue
161APIs are a logical place to transition from one logical core to another in a
162packet processing pipeline.
163
164
165Device Features and Capabilities
166---------------------------------
167
168Crypto devices define their functionality through two mechanisms, global device
169features and algorithm capabilities. Global devices features identify device
170wide level features which are applicable to the whole device such as
171the device having hardware acceleration or supporting symmetric and/or asymmetric
172Crypto operations.
173
174The capabilities mechanism defines the individual algorithms/functions which
175the device supports, such as a specific symmetric Crypto cipher,
176authentication operation or Authenticated Encryption with Associated Data
177(AEAD) operation.
178
179
180Device Features
181~~~~~~~~~~~~~~~
182
183Currently the following Crypto device features are defined:
184
185* Symmetric Crypto operations
186* Asymmetric Crypto operations
187* Chaining of symmetric Crypto operations
188* SSE accelerated SIMD vector operations
189* AVX accelerated SIMD vector operations
190* AVX2 accelerated SIMD vector operations
191* AESNI accelerated instructions
192* Hardware off-load processing
193
194
195Device Operation Capabilities
196~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
197
198Crypto capabilities which identify particular algorithm which the Crypto PMD
199supports are  defined by the operation type, the operation transform, the
200transform identifier and then the particulars of the transform. For the full
201scope of the Crypto capability see the definition of the structure in the
202*DPDK API Reference*.
203
204.. code-block:: c
205
206   struct rte_cryptodev_capabilities;
207
208Each Crypto poll mode driver defines its own private array of capabilities
209for the operations it supports. Below is an example of the capabilities for a
210PMD which supports the authentication algorithm SHA1_HMAC and the cipher
211algorithm AES_CBC.
212
213.. code-block:: c
214
215    static const struct rte_cryptodev_capabilities pmd_capabilities[] = {
216        {    /* SHA1 HMAC */
217            .op = RTE_CRYPTO_OP_TYPE_SYMMETRIC,
218            .sym = {
219                .xform_type = RTE_CRYPTO_SYM_XFORM_AUTH,
220                .auth = {
221                    .algo = RTE_CRYPTO_AUTH_SHA1_HMAC,
222                    .block_size = 64,
223                    .key_size = {
224                        .min = 64,
225                        .max = 64,
226                        .increment = 0
227                    },
228                    .digest_size = {
229                        .min = 12,
230                        .max = 12,
231                        .increment = 0
232                    },
233                    .aad_size = { 0 },
234                    .iv_size = { 0 }
235                }
236            }
237        },
238        {    /* AES CBC */
239            .op = RTE_CRYPTO_OP_TYPE_SYMMETRIC,
240            .sym = {
241                .xform_type = RTE_CRYPTO_SYM_XFORM_CIPHER,
242                .cipher = {
243                    .algo = RTE_CRYPTO_CIPHER_AES_CBC,
244                    .block_size = 16,
245                    .key_size = {
246                        .min = 16,
247                        .max = 32,
248                        .increment = 8
249                    },
250                    .iv_size = {
251                        .min = 16,
252                        .max = 16,
253                        .increment = 0
254                    }
255                }
256            }
257        }
258    }
259
260
261Capabilities Discovery
262~~~~~~~~~~~~~~~~~~~~~~
263
264Discovering the features and capabilities of a Crypto device poll mode driver
265is achieved through the ``rte_cryptodev_info_get`` function.
266
267.. code-block:: c
268
269   void rte_cryptodev_info_get(uint8_t dev_id,
270                               struct rte_cryptodev_info *dev_info);
271
272This allows the user to query a specific Crypto PMD and get all the device
273features and capabilities. The ``rte_cryptodev_info`` structure contains all the
274relevant information for the device.
275
276.. code-block:: c
277
278    struct rte_cryptodev_info {
279        const char *driver_name;
280        uint8_t driver_id;
281        struct rte_device *device;
282
283        uint64_t feature_flags;
284
285        const struct rte_cryptodev_capabilities *capabilities;
286
287        unsigned max_nb_queue_pairs;
288
289        struct {
290            unsigned max_nb_sessions;
291        } sym;
292    };
293
294
295Operation Processing
296--------------------
297
298Scheduling of Crypto operations on DPDK's application data path is
299performed using a burst oriented asynchronous API set. A queue pair on a Crypto
300device accepts a burst of Crypto operations using enqueue burst API. On physical
301Crypto devices the enqueue burst API will place the operations to be processed
302on the devices hardware input queue, for virtual devices the processing of the
303Crypto operations is usually completed during the enqueue call to the Crypto
304device. The dequeue burst API will retrieve any processed operations available
305from the queue pair on the Crypto device, from physical devices this is usually
306directly from the devices processed queue, and for virtual device's from a
307``rte_ring`` where processed operations are placed after being processed on the
308enqueue call.
309
310
311Private data
312~~~~~~~~~~~~
313For session-based operations, the set and get API provides a mechanism for an
314application to store and retrieve the private user data information stored along
315with the crypto session.
316
317For example, suppose an application is submitting a crypto operation with a session
318associated and wants to indicate private user data information which is required to be
319used after completion of the crypto operation. In this case, the application can use
320the set API to set the user data and retrieve it using get API.
321
322.. code-block:: c
323
324	int rte_cryptodev_sym_session_set_user_data(
325		struct rte_cryptodev_sym_session *sess,	void *data, uint16_t size);
326
327	void * rte_cryptodev_sym_session_get_user_data(
328		struct rte_cryptodev_sym_session *sess);
329
330Please note the ``size`` passed to set API cannot be bigger than the predefined
331``user_data_sz`` when creating the session header mempool, otherwise the
332function will return error. Also when ``user_data_sz`` was defined as ``0`` when
333creating the session header mempool, the get API will always return ``NULL``.
334
335For session-less mode, the private user data information can be placed along with the
336``struct rte_crypto_op``. The ``rte_crypto_op::private_data_offset`` indicates the
337start of private data information. The offset is counted from the start of the
338rte_crypto_op including other crypto information such as the IVs (since there can
339be an IV also for authentication).
340
341
342Enqueue / Dequeue Burst APIs
343~~~~~~~~~~~~~~~~~~~~~~~~~~~~
344
345The burst enqueue API uses a Crypto device identifier and a queue pair
346identifier to specify the Crypto device queue pair to schedule the processing on.
347The ``nb_ops`` parameter is the number of operations to process which are
348supplied in the ``ops`` array of ``rte_crypto_op`` structures.
349The enqueue function returns the number of operations it actually enqueued for
350processing, a return value equal to ``nb_ops`` means that all packets have been
351enqueued.
352
353.. code-block:: c
354
355   uint16_t rte_cryptodev_enqueue_burst(uint8_t dev_id, uint16_t qp_id,
356                                        struct rte_crypto_op **ops, uint16_t nb_ops)
357
358The dequeue API uses the same format as the enqueue API of processed but
359the ``nb_ops`` and ``ops`` parameters are now used to specify the max processed
360operations the user wishes to retrieve and the location in which to store them.
361The API call returns the actual number of processed operations returned, this
362can never be larger than ``nb_ops``.
363
364.. code-block:: c
365
366   uint16_t rte_cryptodev_dequeue_burst(uint8_t dev_id, uint16_t qp_id,
367                                        struct rte_crypto_op **ops, uint16_t nb_ops)
368
369
370Operation Representation
371~~~~~~~~~~~~~~~~~~~~~~~~
372
373An Crypto operation is represented by an rte_crypto_op structure, which is a
374generic metadata container for all necessary information required for the
375Crypto operation to be processed on a particular Crypto device poll mode driver.
376
377.. figure:: img/crypto_op.*
378
379The operation structure includes the operation type, the operation status
380and the session type (session-based/less), a reference to the operation
381specific data, which can vary in size and content depending on the operation
382being provisioned. It also contains the source mempool for the operation,
383if it allocated from a mempool.
384
385If Crypto operations are allocated from a Crypto operation mempool, see next
386section, there is also the ability to allocate private memory with the
387operation for applications purposes.
388
389Application software is responsible for specifying all the operation specific
390fields in the ``rte_crypto_op`` structure which are then used by the Crypto PMD
391to process the requested operation.
392
393
394Operation Management and Allocation
395~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
396
397The cryptodev library provides an API set for managing Crypto operations which
398utilize the Mempool Library to allocate operation buffers. Therefore, it ensures
399that the crypto operation is interleaved optimally across the channels and
400ranks for optimal processing.
401A ``rte_crypto_op`` contains a field indicating the pool that it originated from.
402When calling ``rte_crypto_op_free(op)``, the operation returns to its original pool.
403
404.. code-block:: c
405
406   extern struct rte_mempool *
407   rte_crypto_op_pool_create(const char *name, enum rte_crypto_op_type type,
408                             unsigned nb_elts, unsigned cache_size, uint16_t priv_size,
409                             int socket_id);
410
411During pool creation ``rte_crypto_op_init()`` is called as a constructor to
412initialize each Crypto operation which subsequently calls
413``__rte_crypto_op_reset()`` to configure any operation type specific fields based
414on the type parameter.
415
416
417``rte_crypto_op_alloc()`` and ``rte_crypto_op_bulk_alloc()`` are used to allocate
418Crypto operations of a specific type from a given Crypto operation mempool.
419``__rte_crypto_op_reset()`` is called on each operation before being returned to
420allocate to a user so the operation is always in a good known state before use
421by the application.
422
423.. code-block:: c
424
425   struct rte_crypto_op *rte_crypto_op_alloc(struct rte_mempool *mempool,
426                                             enum rte_crypto_op_type type)
427
428   unsigned rte_crypto_op_bulk_alloc(struct rte_mempool *mempool,
429                                     enum rte_crypto_op_type type,
430                                     struct rte_crypto_op **ops, uint16_t nb_ops)
431
432``rte_crypto_op_free()`` is called by the application to return an operation to
433its allocating pool.
434
435.. code-block:: c
436
437   void rte_crypto_op_free(struct rte_crypto_op *op)
438
439
440Symmetric Cryptography Support
441------------------------------
442
443The cryptodev library currently provides support for the following symmetric
444Crypto operations; cipher, authentication, including chaining of these
445operations, as well as also supporting AEAD operations.
446
447
448Session and Session Management
449~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
450
451Sessions are used in symmetric cryptographic processing to store the immutable
452data defined in a cryptographic transform which is used in the operation
453processing of a packet flow. Sessions are used to manage information such as
454expand cipher keys and HMAC IPADs and OPADs, which need to be calculated for a
455particular Crypto operation, but are immutable on a packet to packet basis for
456a flow. Crypto sessions cache this immutable data in a optimal way for the
457underlying PMD and this allows further acceleration of the offload of
458Crypto workloads.
459
460.. figure:: img/cryptodev_sym_sess.*
461
462The Crypto device framework provides APIs to create session mempool and allocate
463and initialize sessions for crypto devices, where sessions are mempool objects.
464The application has to use ``rte_cryptodev_sym_session_pool_create()`` to
465create the session header mempool that creates a mempool with proper element
466size automatically and stores necessary information for safely accessing the
467session in the mempool's private data field.
468
469To create a mempool for storing session private data, the application has two
470options. The first is to create another mempool with elt size equal to or
471bigger than the maximum session private data size of all crypto devices that
472will share the same session header. The creation of the mempool shall use the
473traditional ``rte_mempool_create()`` with the correct ``elt_size``. The other
474option is to change the ``elt_size`` parameter in
475``rte_cryptodev_sym_session_pool_create()`` to the correct value. The first
476option is more complex to implement but may result in better memory usage as
477a session header normally takes smaller memory footprint as the session private
478data.
479
480Once the session mempools have been created, ``rte_cryptodev_sym_session_create()``
481is used to allocate an uninitialized session from the given mempool.
482The session then must be initialized using ``rte_cryptodev_sym_session_init()``
483for each of the required crypto devices. A symmetric transform chain
484is used to specify the operation and its parameters. See the section below for
485details on transforms.
486
487When a session is no longer used, user must call ``rte_cryptodev_sym_session_clear()``
488for each of the crypto devices that are using the session, to free all driver
489private session data. Once this is done, session should be freed using
490``rte_cryptodev_sym_session_free`` which returns them to their mempool.
491
492
493Transforms and Transform Chaining
494~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
495
496Symmetric Crypto transforms (``rte_crypto_sym_xform``) are the mechanism used
497to specify the details of the Crypto operation. For chaining of symmetric
498operations such as cipher encrypt and authentication generate, the next pointer
499allows transform to be chained together. Crypto devices which support chaining
500must publish the chaining of symmetric Crypto operations feature flag. Allocation of the
501xform structure is in the application domain. To allow future API extensions in a
502backwardly compatible manner, e.g. addition of a new parameter, the application should
503zero the full xform struct before populating it.
504
505Currently there are three transforms types cipher, authentication and AEAD.
506Also it is important to note that the order in which the
507transforms are passed indicates the order of the chaining.
508
509.. code-block:: c
510
511    struct rte_crypto_sym_xform {
512        struct rte_crypto_sym_xform *next;
513        /**< next xform in chain */
514        enum rte_crypto_sym_xform_type type;
515        /**< xform type */
516        union {
517            struct rte_crypto_auth_xform auth;
518            /**< Authentication / hash xform */
519            struct rte_crypto_cipher_xform cipher;
520            /**< Cipher xform */
521            struct rte_crypto_aead_xform aead;
522            /**< AEAD xform */
523        };
524    };
525
526The API does not place a limit on the number of transforms that can be chained
527together but this will be limited by the underlying Crypto device poll mode
528driver which is processing the operation.
529
530.. figure:: img/crypto_xform_chain.*
531
532
533Symmetric Operations
534~~~~~~~~~~~~~~~~~~~~
535
536The symmetric Crypto operation structure contains all the mutable data relating
537to performing symmetric cryptographic processing on a referenced mbuf data
538buffer. It is used for either cipher, authentication, AEAD and chained
539operations.
540
541As a minimum the symmetric operation must have a source data buffer (``m_src``),
542a valid session (or transform chain if in session-less mode) and the minimum
543authentication/ cipher/ AEAD parameters required depending on the type of operation
544specified in the session or the transform
545chain.
546
547.. code-block:: c
548
549    struct rte_crypto_sym_op {
550        struct rte_mbuf *m_src;
551        struct rte_mbuf *m_dst;
552
553        union {
554            struct rte_cryptodev_sym_session *session;
555            /**< Handle for the initialised session context */
556            struct rte_crypto_sym_xform *xform;
557            /**< Session-less API Crypto operation parameters */
558        };
559
560        union {
561            struct {
562                struct {
563                    uint32_t offset;
564                    uint32_t length;
565                } data; /**< Data offsets and length for AEAD */
566
567                struct {
568                    uint8_t *data;
569                    rte_iova_t phys_addr;
570                } digest; /**< Digest parameters */
571
572                struct {
573                    uint8_t *data;
574                    rte_iova_t phys_addr;
575                } aad;
576                /**< Additional authentication parameters */
577            } aead;
578
579            struct {
580                struct {
581                    struct {
582                        uint32_t offset;
583                        uint32_t length;
584                    } data; /**< Data offsets and length for ciphering */
585                } cipher;
586
587                struct {
588                    struct {
589                        uint32_t offset;
590                        uint32_t length;
591                    } data;
592                    /**< Data offsets and length for authentication */
593
594                    struct {
595                        uint8_t *data;
596                        rte_iova_t phys_addr;
597                    } digest; /**< Digest parameters */
598                } auth;
599            };
600        };
601    };
602
603Synchronous mode
604----------------
605
606Some cryptodevs support synchronous mode alongside with a standard asynchronous
607mode. In that case operations are performed directly when calling
608``rte_cryptodev_sym_cpu_crypto_process`` method instead of enqueuing and
609dequeuing an operation before. This mode of operation allows cryptodevs which
610utilize CPU cryptographic acceleration to have significant performance boost
611comparing to standard asynchronous approach. Cryptodevs supporting synchronous
612mode have ``RTE_CRYPTODEV_FF_SYM_CPU_CRYPTO`` feature flag set.
613
614To perform a synchronous operation a call to
615``rte_cryptodev_sym_cpu_crypto_process`` has to be made with vectorized
616operation descriptor (``struct rte_crypto_sym_vec``) containing:
617
618- ``num`` - number of operations to perform,
619- pointer to an array of size ``num`` containing a scatter-gather list
620  descriptors of performed operations (``struct rte_crypto_sgl``). Each instance
621  of ``struct rte_crypto_sgl`` consists of a number of segments and a pointer to
622  an array of segment descriptors ``struct rte_crypto_vec``;
623- pointers to arrays of size ``num`` containing IV, AAD and digest information
624  in the ``cpu_crypto`` sub-structure,
625- pointer to an array of size ``num`` where status information will be stored
626  for each operation.
627
628Function returns a number of successfully completed operations and sets
629appropriate status number for each operation in the status array provided as
630a call argument. Status different than zero must be treated as error.
631
632For more details, e.g. how to convert an mbuf to an SGL, please refer to an
633example usage in the IPsec library implementation.
634
635Cryptodev Raw Data-path APIs
636~~~~~~~~~~~~~~~~~~~~~~~~~~~~
637
638The Crypto Raw data-path APIs are a set of APIs designed to enable external
639libraries/applications to leverage the cryptographic processing provided by
640DPDK crypto PMDs through the cryptodev API but in a manner that is not
641dependent on native DPDK data structures (eg. rte_mbuf, rte_crypto_op, ... etc)
642in their data-path implementation.
643
644The raw data-path APIs have the following advantages:
645
646- External data structure friendly design. The new APIs uses the operation
647  descriptor ``struct rte_crypto_sym_vec`` that supports raw data pointer and
648  IOVA addresses as input. Moreover, the APIs does not require the user to
649  allocate the descriptor from mempool, nor requiring mbufs to describe input
650  data's virtual and IOVA addresses. All these features made the translation
651  from user's own data structure into the descriptor easier and more efficient.
652
653- Flexible enqueue and dequeue operation. The raw data-path APIs gives the
654  user more control to the enqueue and dequeue operations, including the
655  capability of precious enqueue/dequeue count, abandoning enqueue or dequeue
656  at any time, and operation status translation and set on the fly.
657
658Cryptodev PMDs which support the raw data-path APIs will have
659``RTE_CRYPTODEV_FF_SYM_RAW_DP`` feature flag presented. To use this feature,
660the user shall create a local ``struct rte_crypto_raw_dp_ctx`` buffer and
661extend to at least the length returned by ``rte_cryptodev_get_raw_dp_ctx_size``
662function call. The created buffer is then initialized using
663``rte_cryptodev_configure_raw_dp_ctx`` function with the ``is_update``
664parameter as 0. The library and the crypto device driver will then set the
665buffer and attach either the cryptodev sym session, the rte_security session,
666or the cryptodev xform for session-less operation into the ctx buffer, and
667set the corresponding enqueue and dequeue function handlers based on the
668algorithm information stored in the session or xform. When the ``is_update``
669parameter passed into ``rte_cryptodev_configure_raw_dp_ctx`` is 1, the driver
670will not initialize the buffer but only update the session or xform and
671the function handlers accordingly.
672
673After the ``struct rte_crypto_raw_dp_ctx`` buffer is initialized, it is now
674ready for enqueue and dequeue operation. There are two different enqueue
675functions: ``rte_cryptodev_raw_enqueue`` to enqueue single raw data
676operation, and ``rte_cryptodev_raw_enqueue_burst`` to enqueue a descriptor
677with multiple operations. In case of the application uses similar approach to
678``struct rte_crypto_sym_vec`` to manage its data burst but with different
679data structure, using the ``rte_cryptodev_raw_enqueue_burst`` function may be
680less efficient as this is a situation where the application has to loop over
681all crypto operations to assemble the ``struct rte_crypto_sym_vec`` descriptor
682from its own data structure, and then the driver will loop over them again to
683translate every operation in the descriptor to the driver's specific queue data.
684The ``rte_cryptodev_raw_enqueue`` should be used to save one loop for each data
685burst instead.
686
687The ``rte_cryptodev_raw_enqueue`` and ``rte_cryptodev_raw_enqueue_burst``
688functions will return or set the enqueue status. ``rte_cryptodev_raw_enqueue``
689will return the status directly, ``rte_cryptodev_raw_enqueue_burst`` will
690return the number of operations enqueued or stored (explained as follows) and
691set the ``enqueue_status`` buffer provided by the user. The possible
692enqueue status values are:
693
694- ``1``: the operation(s) is/are enqueued successfully.
695- ``0``: the operation(s) is/are cached successfully in the crypto device queue
696  but is not actually enqueued. The user shall call
697  ``rte_cryptodev_raw_enqueue_done`` function after the expected operations
698  are stored. The crypto device will then start enqueuing all of them at
699  once.
700- The negative integer: error occurred during enqueue.
701
702Calling ``rte_cryptodev_configure_raw_dp_ctx`` with the parameter ``is_update``
703set as 0 twice without the enqueue function returning or setting enqueue status
704to 1 or ``rte_cryptodev_raw_enqueue_done`` function being called in between will
705invalidate any operation stored in the device queue but not enqueued. This
706feature is useful when the user wants to abandon partially enqueued operations
707for a failed enqueue burst operation and try enqueuing in a whole later.
708
709Similar as enqueue, there are two dequeue functions:
710``rte_cryptodev_raw_dequeue`` for dequeing single operation, and
711``rte_cryptodev_raw_dequeue_burst`` for dequeuing a burst of operations (e.g.
712all operations in a ``struct rte_crypto_sym_vec`` descriptor). The
713``rte_cryptodev_raw_dequeue_burst`` function allows the user to provide callback
714functions to retrieve dequeue count from the enqueued user data and write the
715expected status value to the user data on the fly. The dequeue functions also
716set the dequeue status:
717
718- ``1``: the operation(s) is/are dequeued successfully.
719- ``0``: the operation(s) is/are completed but is not actually dequeued (hence
720  still kept in the device queue). The user shall call the
721  ``rte_cryptodev_raw_dequeue_done`` function after the expected number of
722  operations (e.g. all operations in a descriptor) are dequeued. The crypto
723  device driver will then free them from the queue at once.
724- The negative integer: error occurred during dequeue.
725
726Calling ``rte_cryptodev_configure_raw_dp_ctx`` with the parameter ``is_update``
727set as 0 twice without the dequeue functions execution changed dequeue_status
728to 1 or ``rte_cryptodev_raw_dequeue_done`` function being called in between will
729revert the crypto device queue's dequeue effort to the moment when the
730``struct rte_crypto_raw_dp_ctx`` buffer is initialized. This feature is useful
731when the user wants to abandon partially dequeued data and try dequeuing again
732later in a whole.
733
734There are a few limitations to the raw data path APIs:
735
736* Only support in-place operations.
737* APIs are NOT thread-safe.
738* CANNOT mix the raw data-path API's enqueue with rte_cryptodev_enqueue_burst,
739  or vice versa.
740
741See *DPDK API Reference* for details on each API definitions.
742
743Sample code
744-----------
745
746There are various sample applications that show how to use the cryptodev library,
747such as the L2fwd with Crypto sample application (L2fwd-crypto) and
748the IPsec Security Gateway application (ipsec-secgw).
749
750While these applications demonstrate how an application can be created to perform
751generic crypto operation, the required complexity hides the basic steps of
752how to use the cryptodev APIs.
753
754The following sample code shows the basic steps to encrypt several buffers
755with AES-CBC (although performing other crypto operations is similar),
756using one of the crypto PMDs available in DPDK.
757
758.. code-block:: c
759
760    /*
761     * Simple example to encrypt several buffers with AES-CBC using
762     * the Cryptodev APIs.
763     */
764
765    #define MAX_SESSIONS         1024
766    #define NUM_MBUFS            1024
767    #define POOL_CACHE_SIZE      128
768    #define BURST_SIZE           32
769    #define BUFFER_SIZE          1024
770    #define AES_CBC_IV_LENGTH    16
771    #define AES_CBC_KEY_LENGTH   16
772    #define IV_OFFSET            (sizeof(struct rte_crypto_op) + \
773                                 sizeof(struct rte_crypto_sym_op))
774
775    struct rte_mempool *mbuf_pool, *crypto_op_pool;
776    struct rte_mempool *session_pool, *session_priv_pool;
777    unsigned int session_size;
778    int ret;
779
780    /* Initialize EAL. */
781    ret = rte_eal_init(argc, argv);
782    if (ret < 0)
783        rte_exit(EXIT_FAILURE, "Invalid EAL arguments\n");
784
785    uint8_t socket_id = rte_socket_id();
786
787    /* Create the mbuf pool. */
788    mbuf_pool = rte_pktmbuf_pool_create("mbuf_pool",
789                                    NUM_MBUFS,
790                                    POOL_CACHE_SIZE,
791                                    0,
792                                    RTE_MBUF_DEFAULT_BUF_SIZE,
793                                    socket_id);
794    if (mbuf_pool == NULL)
795        rte_exit(EXIT_FAILURE, "Cannot create mbuf pool\n");
796
797    /*
798     * The IV is always placed after the crypto operation,
799     * so some private data is required to be reserved.
800     */
801    unsigned int crypto_op_private_data = AES_CBC_IV_LENGTH;
802
803    /* Create crypto operation pool. */
804    crypto_op_pool = rte_crypto_op_pool_create("crypto_op_pool",
805                                            RTE_CRYPTO_OP_TYPE_SYMMETRIC,
806                                            NUM_MBUFS,
807                                            POOL_CACHE_SIZE,
808                                            crypto_op_private_data,
809                                            socket_id);
810    if (crypto_op_pool == NULL)
811        rte_exit(EXIT_FAILURE, "Cannot create crypto op pool\n");
812
813    /* Create the virtual crypto device. */
814    char args[128];
815    const char *crypto_name = "crypto_aesni_mb0";
816    snprintf(args, sizeof(args), "socket_id=%d", socket_id);
817    ret = rte_vdev_init(crypto_name, args);
818    if (ret != 0)
819        rte_exit(EXIT_FAILURE, "Cannot create virtual device");
820
821    uint8_t cdev_id = rte_cryptodev_get_dev_id(crypto_name);
822
823    /* Get private session data size. */
824    session_size = rte_cryptodev_sym_get_private_session_size(cdev_id);
825
826    #ifdef USE_TWO_MEMPOOLS
827    /* Create session mempool for the session header. */
828    session_pool = rte_cryptodev_sym_session_pool_create("session_pool",
829                                    MAX_SESSIONS,
830                                    0,
831                                    POOL_CACHE_SIZE,
832                                    0,
833                                    socket_id);
834
835    /*
836     * Create session private data mempool for the
837     * private session data for the crypto device.
838     */
839    session_priv_pool = rte_mempool_create("session_pool",
840                                    MAX_SESSIONS,
841                                    session_size,
842                                    POOL_CACHE_SIZE,
843                                    0, NULL, NULL, NULL,
844                                    NULL, socket_id,
845                                    0);
846
847    #else
848    /* Use of the same mempool for session header and private data */
849	session_pool = rte_cryptodev_sym_session_pool_create("session_pool",
850                                    MAX_SESSIONS * 2,
851                                    session_size,
852                                    POOL_CACHE_SIZE,
853                                    0,
854                                    socket_id);
855
856	session_priv_pool = session_pool;
857
858    #endif
859
860    /* Configure the crypto device. */
861    struct rte_cryptodev_config conf = {
862        .nb_queue_pairs = 1,
863        .socket_id = socket_id
864    };
865
866    struct rte_cryptodev_qp_conf qp_conf = {
867        .nb_descriptors = 2048,
868        .mp_session = session_pool,
869        .mp_session_private = session_priv_pool
870    };
871
872    if (rte_cryptodev_configure(cdev_id, &conf) < 0)
873        rte_exit(EXIT_FAILURE, "Failed to configure cryptodev %u", cdev_id);
874
875    if (rte_cryptodev_queue_pair_setup(cdev_id, 0, &qp_conf, socket_id) < 0)
876        rte_exit(EXIT_FAILURE, "Failed to setup queue pair\n");
877
878    if (rte_cryptodev_start(cdev_id) < 0)
879        rte_exit(EXIT_FAILURE, "Failed to start device\n");
880
881    /* Create the crypto transform. */
882    uint8_t cipher_key[16] = {0};
883    struct rte_crypto_sym_xform cipher_xform = {
884        .next = NULL,
885        .type = RTE_CRYPTO_SYM_XFORM_CIPHER,
886        .cipher = {
887            .op = RTE_CRYPTO_CIPHER_OP_ENCRYPT,
888            .algo = RTE_CRYPTO_CIPHER_AES_CBC,
889            .key = {
890                .data = cipher_key,
891                .length = AES_CBC_KEY_LENGTH
892            },
893            .iv = {
894                .offset = IV_OFFSET,
895                .length = AES_CBC_IV_LENGTH
896            }
897        }
898    };
899
900    /* Create crypto session and initialize it for the crypto device. */
901    struct rte_cryptodev_sym_session *session;
902    session = rte_cryptodev_sym_session_create(session_pool);
903    if (session == NULL)
904        rte_exit(EXIT_FAILURE, "Session could not be created\n");
905
906    if (rte_cryptodev_sym_session_init(cdev_id, session,
907                    &cipher_xform, session_priv_pool) < 0)
908        rte_exit(EXIT_FAILURE, "Session could not be initialized "
909                    "for the crypto device\n");
910
911    /* Get a burst of crypto operations. */
912    struct rte_crypto_op *crypto_ops[BURST_SIZE];
913    if (rte_crypto_op_bulk_alloc(crypto_op_pool,
914                            RTE_CRYPTO_OP_TYPE_SYMMETRIC,
915                            crypto_ops, BURST_SIZE) == 0)
916        rte_exit(EXIT_FAILURE, "Not enough crypto operations available\n");
917
918    /* Get a burst of mbufs. */
919    struct rte_mbuf *mbufs[BURST_SIZE];
920    if (rte_pktmbuf_alloc_bulk(mbuf_pool, mbufs, BURST_SIZE) < 0)
921        rte_exit(EXIT_FAILURE, "Not enough mbufs available");
922
923    /* Initialize the mbufs and append them to the crypto operations. */
924    unsigned int i;
925    for (i = 0; i < BURST_SIZE; i++) {
926        if (rte_pktmbuf_append(mbufs[i], BUFFER_SIZE) == NULL)
927            rte_exit(EXIT_FAILURE, "Not enough room in the mbuf\n");
928        crypto_ops[i]->sym->m_src = mbufs[i];
929    }
930
931    /* Set up the crypto operations. */
932    for (i = 0; i < BURST_SIZE; i++) {
933        struct rte_crypto_op *op = crypto_ops[i];
934        /* Modify bytes of the IV at the end of the crypto operation */
935        uint8_t *iv_ptr = rte_crypto_op_ctod_offset(op, uint8_t *,
936                                                IV_OFFSET);
937
938        generate_random_bytes(iv_ptr, AES_CBC_IV_LENGTH);
939
940        op->sym->cipher.data.offset = 0;
941        op->sym->cipher.data.length = BUFFER_SIZE;
942
943        /* Attach the crypto session to the operation */
944        rte_crypto_op_attach_sym_session(op, session);
945    }
946
947    /* Enqueue the crypto operations in the crypto device. */
948    uint16_t num_enqueued_ops = rte_cryptodev_enqueue_burst(cdev_id, 0,
949                                            crypto_ops, BURST_SIZE);
950
951    /*
952     * Dequeue the crypto operations until all the operations
953     * are processed in the crypto device.
954     */
955    uint16_t num_dequeued_ops, total_num_dequeued_ops = 0;
956    do {
957        struct rte_crypto_op *dequeued_ops[BURST_SIZE];
958        num_dequeued_ops = rte_cryptodev_dequeue_burst(cdev_id, 0,
959                                        dequeued_ops, BURST_SIZE);
960        total_num_dequeued_ops += num_dequeued_ops;
961
962        /* Check if operation was processed successfully */
963        for (i = 0; i < num_dequeued_ops; i++) {
964            if (dequeued_ops[i]->status != RTE_CRYPTO_OP_STATUS_SUCCESS)
965                rte_exit(EXIT_FAILURE,
966                        "Some operations were not processed correctly");
967        }
968
969        rte_mempool_put_bulk(crypto_op_pool, (void **)dequeued_ops,
970                                            num_dequeued_ops);
971    } while (total_num_dequeued_ops < num_enqueued_ops);
972
973Asymmetric Cryptography
974-----------------------
975
976The cryptodev library currently provides support for the following asymmetric
977Crypto operations; RSA, Modular exponentiation and inversion, Diffie-Hellman
978public and/or private key generation and shared secret compute, DSA Signature
979generation and verification.
980
981Session and Session Management
982~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
983
984Sessions are used in asymmetric cryptographic processing to store the immutable
985data defined in asymmetric cryptographic transform which is further used in the
986operation processing. Sessions typically stores information, such as, public
987and private key information or domain params or prime modulus data i.e. immutable
988across data sets. Crypto sessions cache this immutable data in a optimal way for the
989underlying PMD and this allows further acceleration of the offload of Crypto workloads.
990
991Like symmetric, the Crypto device framework provides APIs to allocate and initialize
992asymmetric sessions for crypto devices, where sessions are mempool objects.
993It is the application's responsibility to create and manage the session mempools.
994Application using both symmetric and asymmetric sessions should allocate and maintain
995different sessions pools for each type.
996
997An application can use ``rte_cryptodev_get_asym_session_private_size()`` to
998get the private size of asymmetric session on a given crypto device. This
999function would allow an application to calculate the max device asymmetric
1000session size of all crypto devices to create a single session mempool.
1001If instead an application creates multiple asymmetric session mempools,
1002the Crypto device framework also provides ``rte_cryptodev_asym_get_header_session_size()`` to get
1003the size of an uninitialized session.
1004
1005Once the session mempools have been created, ``rte_cryptodev_asym_session_create()``
1006is used to allocate an uninitialized asymmetric session from the given mempool.
1007The session then must be initialized using ``rte_cryptodev_asym_session_init()``
1008for each of the required crypto devices. An asymmetric transform chain
1009is used to specify the operation and its parameters. See the section below for
1010details on transforms.
1011
1012When a session is no longer used, user must call ``rte_cryptodev_asym_session_clear()``
1013for each of the crypto devices that are using the session, to free all driver
1014private asymmetric session data. Once this is done, session should be freed using
1015``rte_cryptodev_asym_session_free()`` which returns them to their mempool.
1016
1017Asymmetric Sessionless Support
1018~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1019
1020Asymmetric crypto framework supports session-less operations as well.
1021
1022Fields that should be set by user are:
1023
1024Member xform of struct rte_crypto_asym_op should point to the user created rte_crypto_asym_xform.
1025Note that rte_crypto_asym_xform should be immutable for the lifetime of associated crypto_op.
1026
1027Member sess_type of rte_crypto_op should also be set to RTE_CRYPTO_OP_SESSIONLESS.
1028
1029Transforms and Transform Chaining
1030~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1031
1032Asymmetric Crypto transforms (``rte_crypto_asym_xform``) are the mechanism used
1033to specify the details of the asymmetric Crypto operation. Next pointer within
1034xform allows transform to be chained together. Also it is important to note that
1035the order in which the transforms are passed indicates the order of the chaining. Allocation
1036of the xform structure is in the application domain. To allow future API extensions in a
1037backwardly compatible manner, e.g. addition of a new parameter, the application should
1038zero the full xform struct before populating it.
1039
1040Not all asymmetric crypto xforms are supported for chaining. Currently supported
1041asymmetric crypto chaining is Diffie-Hellman private key generation followed by
1042public generation. Also, currently API does not support chaining of symmetric and
1043asymmetric crypto xforms.
1044
1045Each xform defines specific asymmetric crypto algo. Currently supported are:
1046* RSA
1047* Modular operations (Exponentiation and Inverse)
1048* Diffie-Hellman
1049* DSA
1050* None - special case where PMD may support a passthrough mode. More for diagnostic purpose
1051
1052See *DPDK API Reference* for details on each rte_crypto_xxx_xform struct
1053
1054Asymmetric Operations
1055~~~~~~~~~~~~~~~~~~~~~
1056
1057The asymmetric Crypto operation structure contains all the mutable data relating
1058to asymmetric cryptographic processing on an input data buffer. It uses either
1059RSA, Modular, Diffie-Hellman or DSA operations depending upon session it is attached
1060to.
1061
1062Every operation must carry a valid session handle which further carries information
1063on xform or xform-chain to be performed on op. Every xform type defines its own set
1064of operational params in their respective rte_crypto_xxx_op_param struct. Depending
1065on xform information within session, PMD picks up and process respective op_param
1066struct.
1067Unlike symmetric, asymmetric operations do not use mbufs for input/output.
1068They operate on data buffer of type ``rte_crypto_param``.
1069
1070See *DPDK API Reference* for details on each rte_crypto_xxx_op_param struct
1071
1072Asymmetric crypto Sample code
1073-----------------------------
1074
1075There's a unit test application test_cryptodev_asym.c inside unit test framework that
1076show how to setup and process asymmetric operations using cryptodev library.
1077
1078The following sample code shows the basic steps to compute modular exponentiation
1079using 1024-bit modulus length using openssl PMD available in DPDK (performing other
1080crypto operations is similar except change to respective op and xform setup).
1081
1082.. code-block:: c
1083
1084    /*
1085     * Simple example to compute modular exponentiation with 1024-bit key
1086     *
1087     */
1088    #define MAX_ASYM_SESSIONS	10
1089    #define NUM_ASYM_BUFS	10
1090
1091    struct rte_mempool *crypto_op_pool, *asym_session_pool;
1092    unsigned int asym_session_size;
1093    int ret;
1094
1095    /* Initialize EAL. */
1096    ret = rte_eal_init(argc, argv);
1097    if (ret < 0)
1098        rte_exit(EXIT_FAILURE, "Invalid EAL arguments\n");
1099
1100    uint8_t socket_id = rte_socket_id();
1101
1102    /* Create crypto operation pool. */
1103    crypto_op_pool = rte_crypto_op_pool_create(
1104                                    "crypto_op_pool",
1105                                    RTE_CRYPTO_OP_TYPE_ASYMMETRIC,
1106                                    NUM_ASYM_BUFS, 0, 0,
1107                                    socket_id);
1108    if (crypto_op_pool == NULL)
1109        rte_exit(EXIT_FAILURE, "Cannot create crypto op pool\n");
1110
1111    /* Create the virtual crypto device. */
1112    char args[128];
1113    const char *crypto_name = "crypto_openssl";
1114    snprintf(args, sizeof(args), "socket_id=%d", socket_id);
1115    ret = rte_vdev_init(crypto_name, args);
1116    if (ret != 0)
1117        rte_exit(EXIT_FAILURE, "Cannot create virtual device");
1118
1119    uint8_t cdev_id = rte_cryptodev_get_dev_id(crypto_name);
1120
1121    /* Get private asym session data size. */
1122    asym_session_size = rte_cryptodev_get_asym_private_session_size(cdev_id);
1123
1124    /*
1125     * Create session mempool, with two objects per session,
1126     * one for the session header and another one for the
1127     * private asym session data for the crypto device.
1128     */
1129    asym_session_pool = rte_mempool_create("asym_session_pool",
1130                                    MAX_ASYM_SESSIONS * 2,
1131                                    asym_session_size,
1132                                    0,
1133                                    0, NULL, NULL, NULL,
1134                                    NULL, socket_id,
1135                                    0);
1136
1137    /* Configure the crypto device. */
1138    struct rte_cryptodev_config conf = {
1139        .nb_queue_pairs = 1,
1140        .socket_id = socket_id
1141    };
1142    struct rte_cryptodev_qp_conf qp_conf = {
1143        .nb_descriptors = 2048
1144    };
1145
1146    if (rte_cryptodev_configure(cdev_id, &conf) < 0)
1147        rte_exit(EXIT_FAILURE, "Failed to configure cryptodev %u", cdev_id);
1148
1149    if (rte_cryptodev_queue_pair_setup(cdev_id, 0, &qp_conf,
1150                            socket_id, asym_session_pool) < 0)
1151        rte_exit(EXIT_FAILURE, "Failed to setup queue pair\n");
1152
1153    if (rte_cryptodev_start(cdev_id) < 0)
1154        rte_exit(EXIT_FAILURE, "Failed to start device\n");
1155
1156    /* Setup crypto xform to do modular exponentiation with 1024 bit
1157	 * length modulus
1158	 */
1159    struct rte_crypto_asym_xform modex_xform = {
1160		.next = NULL,
1161		.xform_type = RTE_CRYPTO_ASYM_XFORM_MODEX,
1162		.modex = {
1163			.modulus = {
1164				.data =
1165				(uint8_t *)
1166				("\xb3\xa1\xaf\xb7\x13\x08\x00\x0a\x35\xdc\x2b\x20\x8d"
1167				"\xa1\xb5\xce\x47\x8a\xc3\x80\xf4\x7d\x4a\xa2\x62\xfd\x61\x7f"
1168				"\xb5\xa8\xde\x0a\x17\x97\xa0\xbf\xdf\x56\x5a\x3d\x51\x56\x4f"
1169				"\x70\x70\x3f\x63\x6a\x44\x5b\xad\x84\x0d\x3f\x27\x6e\x3b\x34"
1170				"\x91\x60\x14\xb9\xaa\x72\xfd\xa3\x64\xd2\x03\xa7\x53\x87\x9e"
1171				"\x88\x0b\xc1\x14\x93\x1a\x62\xff\xb1\x5d\x74\xcd\x59\x63\x18"
1172				"\x11\x3d\x4f\xba\x75\xd4\x33\x4e\x23\x6b\x7b\x57\x44\xe1\xd3"
1173				"\x03\x13\xa6\xf0\x8b\x60\xb0\x9e\xee\x75\x08\x9d\x71\x63\x13"
1174				"\xcb\xa6\x81\x92\x14\x03\x22\x2d\xde\x55"),
1175				.length = 128
1176			},
1177			.exponent = {
1178				.data = (uint8_t *)("\x01\x00\x01"),
1179				.length = 3
1180			}
1181		}
1182    };
1183    /* Create asym crypto session and initialize it for the crypto device. */
1184    struct rte_cryptodev_asym_session *asym_session;
1185    asym_session = rte_cryptodev_asym_session_create(asym_session_pool);
1186    if (asym_session == NULL)
1187        rte_exit(EXIT_FAILURE, "Session could not be created\n");
1188
1189    if (rte_cryptodev_asym_session_init(cdev_id, asym_session,
1190                    &modex_xform, asym_session_pool) < 0)
1191        rte_exit(EXIT_FAILURE, "Session could not be initialized "
1192                    "for the crypto device\n");
1193
1194    /* Get a burst of crypto operations. */
1195    struct rte_crypto_op *crypto_ops[1];
1196    if (rte_crypto_op_bulk_alloc(crypto_op_pool,
1197                            RTE_CRYPTO_OP_TYPE_ASYMMETRIC,
1198                            crypto_ops, 1) == 0)
1199        rte_exit(EXIT_FAILURE, "Not enough crypto operations available\n");
1200
1201    /* Set up the crypto operations. */
1202    struct rte_crypto_asym_op *asym_op = crypto_ops[0]->asym;
1203
1204	/* calculate mod exp of value 0xf8 */
1205    static unsigned char base[] = {0xF8};
1206    asym_op->modex.base.data = base;
1207    asym_op->modex.base.length = sizeof(base);
1208	asym_op->modex.base.iova = base;
1209
1210    /* Attach the asym crypto session to the operation */
1211    rte_crypto_op_attach_asym_session(op, asym_session);
1212
1213    /* Enqueue the crypto operations in the crypto device. */
1214    uint16_t num_enqueued_ops = rte_cryptodev_enqueue_burst(cdev_id, 0,
1215                                            crypto_ops, 1);
1216
1217    /*
1218     * Dequeue the crypto operations until all the operations
1219     * are processed in the crypto device.
1220     */
1221    uint16_t num_dequeued_ops, total_num_dequeued_ops = 0;
1222    do {
1223        struct rte_crypto_op *dequeued_ops[1];
1224        num_dequeued_ops = rte_cryptodev_dequeue_burst(cdev_id, 0,
1225                                        dequeued_ops, 1);
1226        total_num_dequeued_ops += num_dequeued_ops;
1227
1228        /* Check if operation was processed successfully */
1229        if (dequeued_ops[0]->status != RTE_CRYPTO_OP_STATUS_SUCCESS)
1230                rte_exit(EXIT_FAILURE,
1231                        "Some operations were not processed correctly");
1232
1233    } while (total_num_dequeued_ops < num_enqueued_ops);
1234
1235
1236Asymmetric Crypto Device API
1237~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1238
1239The cryptodev Library API is described in the
1240`DPDK API Reference <https://doc.dpdk.org/api/>`_
1241